IEMed Mediterranean Yearbook 2008

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Panorama: The Mediterranean Year

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Resources and Water Demand. Forecasts for the Future of Water in the Mediterranean

Mohammed Blinda

Water Programme Officer,
Blue Plan for the Mediterranean, Valbonne

An essential resource for humanity and for ecological balance, water is at the core of the problem of sustainable development. Its management in the Mediterranean area, where it is unequally distributed in time and space, is today characterised by non-sustainable forms of production and consumption, frequent failure to take into account the long term, and policies chiefly concerned with the water offer. Today these approaches are reaching their limit and are coming up against growing social, economic and ecological obstacles in almost all the Mediterranean countries.

Resources are already being overexploited in many places, and there will continue to be significant increasing water requirements as a result of the population growth in the South and East and with the development of tourism, industry and irrigated areas.

Within the context of a growing water shortage in part of the region, and in the light of the uncertainties arising from the climate change, the Mediterranean countries are now confronted with several challenges: sustainable management of limited resources, ensuring access to drinking water for the population groups who are not yet supplied, and raising the users’ awareness of the importance of water-saving habits.

The first of these challenges means implementing water demand management policies able to reduce loss and inefficient use, managing the resource fairly and assuring its different uses are catered for. An increase in the water offer will also presumably be necessary, to be organised through improved resource management (increasing the amount of potentially usable water and combating pollution) or through non-conventional forms of water supply (recycling of treated waste water and desalination of sea or brackish water). The second challenge involves putting the Millennium Development Goals into practice as regards access to drinking water and sanitation. The third calls for reinforcement of the partnerships between the users and the local water management organisations, together with water saving awareness-raising campaigns geared towards the former.

The work of the Blue Plan, and the recommendations resulting from the regional workshop it organised in 2007 with its regional water sector partners, highlights the pressing need for adaptation of water management policies, improved administration of the different uses and a more economical, efficient use of resources, in order to respond to the population’s demand and the need for development in the present and future.  

Water Resources in the Mediterranean Region

Fragile, Irregular Water Resources

The conventional renewable water resources – the so-called “natural” water resources – of the group of Mediterranean countries are globally estimated to be around 1,080 km3 per year, for an average year.

The most important issue is the conspicuous unbalance in the geographical distribution of these resources:

  • two thirds (2/3) are located in the North
  • a quarter (1/4) are located in the East
  • a tenth (1/10) are located in the South.

The group of 6 countries with the shortest supply (Cyprus, Israel, Libya, Malta, the Palestinian Territories and Tunisia) possesses less than 1% of the whole.

The Mediterranean is home to 60% of the world’s “poor” with regard to water (those with less than 1,000 m3 per inhabitant per year) and twenty million people currently without access to drinking water, particularly in the southern and eastern countries.

Overall, 28% of these resources, i.e. some 300 km3 per year, cross the borders and are common to several countries, Mediterranean and others. The rate of dependence on external resources is particularly high in some of the countries: 97% in Egypt (the Nile), 55% in Israel (the Jordan, Mountain Aquifer), 47% in Croatia, and 43% in Syria (the Euphrates).

However, quantifying water resources by annual averages by no means presents a whole picture of the situation, and the gaps are more significant than the averages: with the Mediterranean climate, the annual amounts vary greatly according to wet and dry years; in 9 out of 10 years the minimum assured resources, corresponding to the amounts for a decennial dry year, can fall to a third or a quarter of the average. The variability differences between seasons and years, more marked in the southern and eastern regions, increase this contrast.

The resources should not merely be restricted to “blue waters,” i.e. surface or ground water sources; the “green waters” proceeding directly from rainfall, with an average annual flow of up to 400 – 500 km3 per year in the Mediterranean countries, should also be taken into account. These resources have a similarly unequal distribution: 65% in the North, 20% in the East, and 15% in the South. These figures explain the increase in the demand for irrigation water in the eastern and southern countries, often over 60% and reaching almost 90% in some countries.

Indicators to Illustrate Water Resource Evaluation

The competition indicator and the inverse ratio – the index of resources per inhabitant – are very sensitive to population variations and are in general an efficient expression of the relative wealth or scarcity of water in a country. These indicators are of practical use for comparisons on a national level, and particularly for forecasting purposes, as they rest on the only demographic variable, which is relatively easy to forecast. The figure for “natural” water resources per inhabitant is the first indicator able to define situations of “water stress” or “scarcity” (1,000/500 m3 per head per year) and “structural shortage” (less than 500 m3 per year per head). The differences between countries and between interior regions or basins are even greater. For example, the natural resources per inhabitant in Montenegro (a Mediterranean record: over 25,000 m3 per year) are 500 times greater than those of Gaza, the territory with the least resources!

TABLE 1 Renewable and Usable Water Resources in the Mediterranean Region (2004)

North (Europe)East (Near East)South (North Africa)Overall
“Natural” renewable resources, “blue water” (annual averages) (a)km3 per year %740 68247 2395 91,083 100
Per inhabitant m3 per year3,9152,3716312,441
Average competition indexNo. of inhabitants per hm3 per year of resources2554221,584410
Usable resources (annual averages) (b)km3 per year35913381572
Per inhabitant m3 per year1,8991,2795361,289
In comparison: Average “green water” in km3 per year (c)30010070470

Source: Blue Plan, 2007. (a) Internal and external resources, calculated by sub-regions. Exchanges between bordering Mediterranean countries have not been counted twice; (b) According to each country’s particular criteria; (c) Rainwater used and consumed (evapotranspired) by irrigated agriculture and pastureland.

This unbalance is further increased if we express water availability by calculating how many inhabitants need to share each million m3 per year. This competition indicator varies from 40 inhabitants in Montenegro to 25,000 in Gaza!

This stress affecting water resources is even more important when we consider that not all of the natural renewable water resources are necessarily “usable.” In practice, genuinely usable water resources represent around a half or a third of the renewable natural resources. This phenomenon is due to practical limitations (only a third of the whole consists of regular flows), and others of a socio-economic and environmental nature (particularly for the conservation of the aquatic eco-systems). The key figures in table 1 sum up the contrasts between sub-regions.

Water Demand and Use in the Mediterranean

Total Water Demand

The approximately 281 km3 per year used by the inhabitants of the Mediterranean is also unequally distributed, less so between the North and the South-South-East than between consumer sectors. Irrigation greatly prevails in the South and the East: 81%, as opposed to the 64% on average for the region as a whole.

As regards demand per inhabitant, while this seems quite similar on average per sub-region, it is much more contrasted when calculated by countries: it varies from over 1,000 m3 per year (Egypt) to under 100 m3 per year (West Bank, Montenegro, Croatia). There again, the variation in the relative weighting of irrigation explains most of the differences.

TABLE 2 Current Water Demand in the Mediterranean Countries

NorthEastSouthOverall
Communities (drinking water)22.38.77.938.9
Irrigated agriculture57.74776.6181.3
Industries not served13.62.23.419.2
Energy (cooling)34.12.54.941.5
TOTAL127.760.492.8280.9
Evaporation of reservoirs (approximate) in km3 per year571223
Sum total (rounded off) in km3 per year13367105304
2004 populations in millions of inhab.189104151444
Average demand (of the 4 sectors) per inhabitant in m3 per year676580618633

Source: Blue Plan, 2007. The key figures in table 2, in which we have considered it relevant to include the net consumption by evaporation of the dam reservoirs (the real supplementary evaporation resulting from the creation of reservoirs is calculated by the difference between the annual averages for potential evapotranspiration and real evapotranspiration applied to the air used); the total average flow for this in accordance with the world register of dams (ICOLD) should be around 20/25 km3 per year in the region as a whole.

Like the resources, the demand calculated per basin is marked by significant unbalances: the record for demand per inhabitant is in Spain, in the Ebro basin: 3700 m3 per year in around 2000.

Water demand is not linked to levels of socio-economic development, and the most developed countries do not use more water than the “developing” countries; in fact the opposite is true. Compared with each dollar of agricultural added value, the annual amounts of water used for irrigation range from around 15 litres in Slovenia to over 3000 litres in Syria and in Egypt. 

Water Demand for Agriculture

Analysis of per-sector demand shows that in most of the countries, the main user in terms of volume is still agriculture (irrigation), except in the eastern Adriatic countries and France.

The demand for irrigation water (Table 3) shows a diversity of situations. In the temperate countries, irrigation water withdrawals are not very significant (12% of the total for France). However, the dryer the climate is, the more agriculture needs to resort to irrigation (blue water) and the more its part of the total withdrawal increases. Values of around 80/90% of the total demand for blue water are registered in certain countries in the South and East. This fact highlights the importance of rainfed agriculture (green water), which is not properly exploited and should be valued in the semi-arid and arid countries. Improving the efficiency of rainfed agriculture through conservation of the water and the soils would lead to an increase in the soil’s rain water storage capacity and would consequently limit the need for irrigation contribution, while at the same time reducing erosion and the consequent silting up of the reserves downstream.

TABLE 3 Water Demand for Agriculture in the Mediterranean Countries

NorthEastSouthOverall
Irrigated agriculture (blue water) in km3 per year57.74776.6181.3
Demand for green water (rainfed agriculture) in km3 per year27610170447
Water demand for agriculture in km3 per year334148146629

Source: Blue Plan, 2007

The irrigated surface areas in the Mediterranean countries, and the irrigation water demand per irrigated hectare, show that the proportions vary greatly from one country to another (Map 1). In 2007, around 182 billion m3 of water was used for irrigating some 24 million hectares as compared with 11 million ha in 1961 (WWF, 2006), which represents an average water demand per hectare of around 7500 m3.

MAP 1 Irrigated Surface Areas in the Mediterranean Countries (in 1000 ha)

Source: Blue Plan, Aquasat, 2008

The form in which irrigation is carried out is also very variable, the main part corresponding to gravity irrigation (in terms of surface area, and even more so in terms of volume). However, over the last few years considerable efforts have been remarked with regard to pressure networks such as sprinkling and localised irrigation in the most of the southern and eastern countries. The map below shows the amounts of water-saving equipment in the irrigated surface areas (Map 2).

MAP 2 Irrigated Surfaces Equipped with Water-Saving Equipment 

Source: Blue Plan, Aquasat, 2008

At least in theory, there is considerable room for progress, which may in fact involve irrigation output and the form of irrigation. As regards the latter, the consumption in m3 per hectare per year varies greatly:

TABLE 4 Variation in Consumption in m3 per Hectare per Year

 Consumption in m3 per ha per year  
Gravity irrigation5,000 – 20,000
Sprinkler irrigation1,500 – 5,000
Localised irrigation1,000 – 3,000

Source: (FAO, 1999)

Even though the water transported to the plot in excess of the plants’ requirements is reused in certain cases (irrigation by groundwater pumping or runoff), changing the form of irrigation can, more often than not, lead to significant water savings.

The degree of pressure exerted by the demand on the resources can be seen by the way in which agriculture, and particularly plot irrigation, is practised. The water consumption index per hectare calculated for the Mediterranean countries between 2000 and 2005 reveals a great diversity of situations (Chart 1):

A 1st group of countries whose water consumption per hectare is between 5,000 and 20,000 m3.

A 2nd group of countries with a per-hectare water demand between 3,000 and 5,000 m3.

A 3rd group of countries whose water consumption per hectare is under 3,000 m3.

CHART 1 Demand for Irrigation Water per Irrigated Hectare

Source: Blue Plan, 2007

Efficiency of Water Use

In spite of some encouraging progress (Chart 2), the current returns from water use are far from satisfactory; throughout the Mediterranean region, losses and leakages in transport, inefficient irrigation practices and squandering are estimated to be in excess of 100 km3 per year, i.e. some 45% of the total water demand (281 km3 per year) (Table 5).

TABLE 5 Current Losses and Inefficient Use of Water Withdrawn for the Drinking Water Distribution and Irrigation Sectors only (in km3 per year)

NorthEastSouthkm3 per year%
Irrigated agriculture2524469587
Communities
(drinking water)
7431413
Overall322849109100

Source: Blue Plan 2007, based on national sources.

This is equivalent to a potential “pool” of considerable water savings, of which at least part could be mobilised by a more active “water demand management” policy (increased efficiency of water use).

CHART 2 Efficiency of Water Use (Total and by Consumer Sectors) in the Mediterranean Countries

Source: Blue Plan (data currently being validated)

Demand with Respect to Water Resources

Increasing Pressure on Water Resources

To evaluate the degree of water stress or shortage, these studies are based on two classic indicators (Table 6): on the one hand, renewable water resources (natural or usable) per inhabitant (M. Falkenmark, 1997), and on the other hand the use index for renewable natural resources (ratio of withdrawal to resources) each matched with revealing thresholds:

TABLE 6 Thresholds for Water Stress and Scarcity Situations

SituationAverage renewable natural resources (m3 per inhabitant per year)Index of use of renewable natural resources (%)
Water stress, water shortage500 – 1,00050 – 100
Water scarcity< 500³ 100

Source: Blue Plan, 2007

The average use indexes in each country suffering this pressure are a new indicator of situations of water stress (above 50%) or scarcity (approaching or even exceeding 100%), and are fairly well correlated with the resources per inhabitant.

In accordance with these criteria, all the southern and many of the eastern Mediterranean countries have currently surpassed the stress threshold, and six of them (Algeria, the Palestinian Territories, Israel, Libya, Malta and Tunisia) are in a scarcity situation.

The use indexes calculated by country have revealed three different situations (Chart 2): a first group of countries in which the ratio is under 25%, a second group of countries with a ratio of between 25 and 50%, and a third group of countries where water withdrawals approach or even exceed the limit level of renewable resources (ratio > 75%). These use indexes, calculated on a national level, may hide major disparities as regards the catchment area or on a local level, as is the case in certain countries in the North (Mediterranean Spain, southern Italy, etc.).

CHART 3 Index of Use of Renewable Natural Resources (2000- 2005) in %

Source: Blue Plan 2007

The current pressure of water withdrawals – essential sources of water supply in most of the Mediterranean countries – are naturally highly unsymmetrical, as the demand is higher wherever there are less resources.

Table 7 shows the average values for another pressure indicator (the index of final consumption of the renewable resources) and again highlights the differences between sub-regions, although the averages by countries are further contrasted.

TABLE 7 Current Pressure on the Average Renewable Water Resources

NorthEastSouthOverall
Current withdrawals in km3 per year11286172261
Average use index (%)16267623
Final consumptions in km3 per year423364139
Average final consumption index (%)6136712

Source: Blue Plan, 2007 1 Withdrawals from renewable resources only. Withdrawals from non-renewable or “secondary” resources (water returns) and the resulting final consumptions are not taken into account here.

At present, the total demand approaches or exceeds the renewable resources in several southern and eastern countries, where they are partially covered by the use of non-renewable or non-conventional resources: this is the case in Egypt, Gaza, Israel, Libya and Malta.

Developments Incompatible with Those of Water Availability

According to the forecasts made in the Blue Plan (baseline trend scenario), the water demand could be increased by a further 50 km3, reaching 332 km3 by 2025 (i.e. 18% of the current demand), with the South and the East bank countries at the root of this growth (Chart 4). Agriculture should remain the principal user of the water resources, in terms of volume, for satisfying irrigation requirements, particularly in the South and East of the basin. According to the FAO, irrigated surface areas could increase by 38% in the South and by 58% in the East by 2030, while the demand for agricultural water will only slightly increase or remain stable in the North.

CHART 4 Total Water Demand, Baseline and Alternative Scenarios (by Whole Countries)

Source: Blue Plan, 2007

 Given the essential nature of the drinking water supply, urban demand will undergo rapid, significant growth as regards allocation of resources and investment. In the southern and eastern Mediterranean countries, the urbanisation rate has in general exceeded 50% of the total population; it is increasing very rapidly and within twenty or thirty years is expected to reach the “ceiling” of 70/80% which the northern countries will soon have attained. Likewise, in the space of a generation, the population of the Mediterranean countries should increase by 10 million in the North and by 82 million in the South and East, reaching 535 million inhabitants by 2025.

Furthermore, with some 300 million tourists in 2025 in the Mediterranean coastal regions, which will remain the world’s top tourist destinations, tourism has the effect of increasing the demand for drinking water in the receiving areas: in luxury hotels it is 500/800 litres per person per day, much higher than that of the permanent residents. Golf courses consume as much water per hectare as well-irrigated areas do (7,000/10,000 m3 per hectare per year).

Industry, although it uses a lesser amount, is also set to increase its water consumption. This is the case for the Algerian paper pulp factories, for example, which are huge water consumers (just one factory consumes 30 million m3 per year, equivalent to a town of half a million inhabitants); and certain areas have significant projects for industrial development.

While it is difficult to quantify, the environmental demand – mainly used for the correct functioning of the ecosystems – could take on great importance. Certain countries have already included the earmarking of a minimum flow of the watercourses for species protection in their legislation (France), or have explicitly included environmental demand (Spain), and others could follow (Italy, Israel, Morocco, Tunisia, etc.).

The unequal tendencies towards growth in demand are expected to spread and worsen the unbalances, particularly in the South and the Near East. So, even if the water resources remained unchanged, the populations in a situation of water stress or scarcity could increase to 250 million by 2025 (i.e. 47%), from a total population of 535 million in the Mediterranean countries, according to forecasts made by the United Nations, and this would be even more so in the case of impoverishment of the conventional water resources. In 2050, all the countries in the South will be in a scarcity situation (Egypt and Morocco will have joined those already on the list).

Water scarcity situations are already the case in part of the Mediterranean region and they will inevitably spread and worsen in the twenty-first century, especially in the South and the East: the countries whose water resources are already the lowest per inhabitant and the most expensive to mobilise and distribute will experience the greatest increase in demand, and will run the greatest risk of their resources becoming impoverished. This means considerable efforts will have to be made to adapt to the new Mediterranean contexts (economy, forms of development).

The margins for choice of water policies in the Mediterranean region are not huge, but they do exist. The policies should be modified towards a rebalance between the offer-orientated approach, which has long predominated, and an approach geared towards demand management.

Ideas for Saving a Quarter of the Water Demand

As water management is also a political issue, these trends cannot be ignored. They can be mitigated by policies especially geared towards improving the efficiency with which resources are used and further diminishing losses and inefficient use, particularly in irrigation, where the average efficiency of water use on a plot barely exceeds 60% and in some towns leakage is estimated to be as high as 40%.

The room for progress in this issue is considerable, as improved water demand management (the Blue Plan alternative scenario) would enable savings of a quarter of the demand, i.e. some 86 km3 per year by 2025 (Chart 4 and Chart 5).

Irrigated agriculture represents the greatest potential for savings in terms of volume, with almost 65% of the total water saving potential identified in the Mediterranean area (transport losses reduced to half, reaching 10%, efficiency in transporting irrigation water to the plots increased from 60% to 80%). The rest of the potential water savings involve industry, representing 22% (recycling rates reduced to 50%), and the supply of drinking water, with 13% (reduction by half in transport losses and leakage affecting users, reaching 15% and 10% respectively).

In the light of this optimistic perspective, theoretically generalised in all the Mediterranean countries, the total water demand could reach 246 km3 per year (102 km3 per year in the North and 144 km3 per year in the South and the Near East), which would be the overall equivalent of a reduction in the total demand of some 40 km3 per year with respect to 2005 (Chart 6).

CHART 5 Demand by Consumer Sector, Baseline and Alternative Scenarios, Whole Countries

Source: Blue Plan, 2007

Essential Reforms for Trend Improvement

The switch from a trend scenario to a more durable development scenario can only be made progressively, through essential reforms with the clear objective of integrated water resource management in all the policies – and in the agricultural policies particularly – and generating the means for it to be put into practice, basically establishing efficiency plans and sustainable financing systems.

Within this context, the question of financing investment in drinking water supplies and sanitation (in the South and East), and the use of financial instruments – subsidies, pricing, etc. – to optimise allocation of available resources are vital for the future. The same applies to the reinforcement of management capacities, particularly on a local level. Regional cooperation, benefiting from a long-standing tradition in the water policy field in the Mediterranean area, is in a position to contribute to catalysing and accelerating the desired changes.

The recommendations of the regional workshop organised by the Blue Plan and its partners (see box), adopted by the Mediterranean Commission on Sustainable Development (May 2007) and later by the Mediterranean countries as a whole and the European Community at the 15th meeting of Contracting Parties to the Barcelona Convention (January 2008), are aimed at the political decision-makers, given the essential nature of their role in promotion of water demand management (WDM). They place particular stress on the need to raise WDM to the rank of a strategic national priority, to assure its promotion and to coordinate its definition, follow-up and evaluation within the policies of the different sectors, particularly those of agriculture, energy, tourism, the environment and land planning.

References

Benoit, Guillaume and Comeau, Aline (directed by). Méditerranée, les perspectives du Plan Bleu sur l’environnement et le développement, ed. de l’Aube, pp.71-107, 2005.

Blinda, Mohammed and Thivet, Gaëlle. Faire face aux crises et pénuries d’eau en Méditerranée, Les Notes du Plan Bleu, no. 4, 2006.

Margat, Jean. “L’eau des Méditerranéens: situation et perspectives”, Blue Plan, MAP Technical Report Series no. 158, p. 330, Athens, 2004.

Margat, Jean and Blinda, Mohammed. L’avenir de l’eau en Méditerranée. Problèmes et solutions: nouvelle prospective 2025 du Plan Bleu. «International Conference on Water, land and Food Security in Arid and Semi-arid Regions», Keynote papers: 47-63 (2005).

Food and Agriculture organisation of the United Nations (FAO). Agriculture: toward 2015/2030, Global perspective studies unit, 2000.

Blue Plan. Water demand management in the Mediterranean, progress and policies. Proceedings of the 3rd regional workshop on water and sustainable development in the Mediterranean (2007).

Blue Plan. “Water demand management in the Mediterranean, progress and policies.” MAP Technical Report Series no. 168, Athens, 2008.